fs/btrfs/ordered-data.h

   1 /*
   2  * Copyright (C) 2007 Oracle.  All rights reserved.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public
   6  * License v2 as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11  * General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public
  14  * License along with this program; if not, write to the
  15  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  16  * Boston, MA 021110-1307, USA.
  17  */
  18
  19 #ifndef __BTRFS_ORDERED_DATA__
  20 #define __BTRFS_ORDERED_DATA__
  21
  22 /* one of these per inode */
  23 struct btrfs_ordered_inode_tree {
  24         spinlock_t lock;
  25         struct rb_root tree;
  26         struct rb_node *last;
  27 };
  28
  29 struct btrfs_ordered_sum {
  30         /* bytenr is the start of this extent on disk */
  31         u64 bytenr;
  32
  33         /*
  34          * this is the length in bytes covered by the sums array below.
  35          */
  36         int len;
  37         struct list_head list;
  38         /* last field is a variable length array of csums */
  39         u32 sums[];
  40 };
  41
  42 /*
  43  * bits for the flags field:
  44  *
  45  * BTRFS_ORDERED_IO_DONE is set when all of the blocks are written.
  46  * It is used to make sure metadata is inserted into the tree only once
  47  * per extent.
  48  *
  49  * BTRFS_ORDERED_COMPLETE is set when the extent is removed from the
  50  * rbtree, just before waking any waiters.  It is used to indicate the
  51  * IO is done and any metadata is inserted into the tree.
  52  */
  53 #define BTRFS_ORDERED_IO_DONE 0 /* set when all the pages are written */
  54
  55 #define BTRFS_ORDERED_COMPLETE 1 /* set when removed from the tree */
  56
  57 #define BTRFS_ORDERED_NOCOW 2 /* set when we want to write in place */
  58
  59 #define BTRFS_ORDERED_COMPRESSED 3 /* writing a zlib compressed extent */
  60
  61 #define BTRFS_ORDERED_PREALLOC 4 /* set when writing to prealloced extent */
  62
  63 #define BTRFS_ORDERED_DIRECT 5 /* set when we're doing DIO with this extent */
  64
  65 #define BTRFS_ORDERED_IOERR 6 /* We had an io error when writing this out */
  66
  67 #define BTRFS_ORDERED_UPDATED_ISIZE 7 /* indicates whether this ordered extent
  68                                        * has done its due diligence in updating
  69                                        * the isize. */
  70 #define BTRFS_ORDERED_LOGGED_CSUM 8 /* We've logged the csums on this ordered
  71                                        ordered extent */
  72 #define BTRFS_ORDERED_TRUNCATED 9 /* Set when we have to truncate an extent */
  73
  74 #define BTRFS_ORDERED_LOGGED 10 /* Set when we've waited on this ordered extent
  75                                  * in the logging code. */
  76 struct btrfs_ordered_extent {
  77         /* logical offset in the file */
  78         u64 file_offset;
  79
  80         /* disk byte number */
  81         u64 start;
  82
  83         /* ram length of the extent in bytes */
  84         u64 len;
  85
  86         /* extent length on disk */
  87         u64 disk_len;
  88
  89         /* number of bytes that still need writing */
  90         u64 bytes_left;
  91
  92         /* number of bytes that still need csumming */
  93         u64 csum_bytes_left;
  94
  95         /*
  96          * the end of the ordered extent which is behind it but
  97          * didn't update disk_i_size. Please see the comment of
  98          * btrfs_ordered_update_i_size();
  99          */
 100         u64 outstanding_isize;
 101
 102         /*
 103          * If we get truncated we need to adjust the file extent we enter for
 104          * this ordered extent so that we do not expose stale data.
 105          */
 106         u64 truncated_len;
 107
 108         /* flags (described above) */
 109         unsigned long flags;
 110
 111         /* compression algorithm */
 112         int compress_type;
 113
 114         /* reference count */
 115         atomic_t refs;
 116
 117         /* the inode we belong to */
 118         struct inode *inode;
 119
 120         /* list of checksums for insertion when the extent io is done */
 121         struct list_head list;
 122
 123         /* If we need to wait on this to be done */
 124         struct list_head log_list;
 125
 126         /* If the transaction needs to wait on this ordered extent */
 127         struct list_head trans_list;
 128
 129         /* used to wait for the BTRFS_ORDERED_COMPLETE bit */
 130         wait_queue_head_t wait;
 131
 132         /* our friendly rbtree entry */
 133         struct rb_node rb_node;
 134
 135         /* a per root list of all the pending ordered extents */
 136         struct list_head root_extent_list;
 137
 138         struct btrfs_work work;
 139
 140         struct completion completion;
 141         struct btrfs_work flush_work;
 142         struct list_head work_list;
 143 };
 144
 145 /*
 146  * calculates the total size you need to allocate for an ordered sum
 147  * structure spanning 'bytes' in the file
 148  */
 149 static inline int btrfs_ordered_sum_size(struct btrfs_root *root,
 150                                          unsigned long bytes)
 151 {
 152         int num_sectors = (int)DIV_ROUND_UP(bytes, root->sectorsize);
 153         return sizeof(struct btrfs_ordered_sum) + num_sectors * sizeof(u32);
 154 }
 155
 156 static inline void
 157 btrfs_ordered_inode_tree_init(struct btrfs_ordered_inode_tree *t)
 158 {
 159         spin_lock_init(&t->lock);
 160         t->tree = RB_ROOT;
 161         t->last = NULL;
 162 }
 163
 164 void btrfs_put_ordered_extent(struct btrfs_ordered_extent *entry);
 165 void btrfs_remove_ordered_extent(struct inode *inode,
 166                                 struct btrfs_ordered_extent *entry);
 167 int btrfs_dec_test_ordered_pending(struct inode *inode,
 168                                    struct btrfs_ordered_extent **cached,
 169                                    u64 file_offset, u64 io_size, int uptodate);
 170 int btrfs_dec_test_first_ordered_pending(struct inode *inode,
 171                                    struct btrfs_ordered_extent **cached,
 172                                    u64 *file_offset, u64 io_size,
 173                                    int uptodate);
 174 int btrfs_add_ordered_extent(struct inode *inode, u64 file_offset,
 175                              u64 start, u64 len, u64 disk_len, int type);
 176 int btrfs_add_ordered_extent_dio(struct inode *inode, u64 file_offset,
 177                                  u64 start, u64 len, u64 disk_len, int type);
 178 int btrfs_add_ordered_extent_compress(struct inode *inode, u64 file_offset,
 179                                       u64 start, u64 len, u64 disk_len,
 180                                       int type, int compress_type);
 181 void btrfs_add_ordered_sum(struct inode *inode,
 182                            struct btrfs_ordered_extent *entry,
 183                            struct btrfs_ordered_sum *sum);
 184 struct btrfs_ordered_extent *btrfs_lookup_ordered_extent(struct inode *inode,
 185                                                          u64 file_offset);
 186 void btrfs_start_ordered_extent(struct inode *inode,
 187                                 struct btrfs_ordered_extent *entry, int wait);
 188 int btrfs_wait_ordered_range(struct inode *inode, u64 start, u64 len);
 189 struct btrfs_ordered_extent *
 190 btrfs_lookup_first_ordered_extent(struct inode * inode, u64 file_offset);
 191 struct btrfs_ordered_extent *btrfs_lookup_ordered_range(struct inode *inode,
 192                                                         u64 file_offset,
 193                                                         u64 len);
 194 int btrfs_ordered_update_i_size(struct inode *inode, u64 offset,
 195                                 struct btrfs_ordered_extent *ordered);
 196 int btrfs_find_ordered_sum(struct inode *inode, u64 offset, u64 disk_bytenr,
 197                            u32 *sum, int len);
 198 int btrfs_wait_ordered_extents(struct btrfs_root *root, int nr);
 199 void btrfs_wait_ordered_roots(struct btrfs_fs_info *fs_info, int nr);
 200 void btrfs_get_logged_extents(struct inode *inode,
 201                               struct list_head *logged_list,
 202                               const loff_t start,
 203                               const loff_t end);
 204 void btrfs_put_logged_extents(struct list_head *logged_list);
 205 void btrfs_submit_logged_extents(struct list_head *logged_list,
 206                                  struct btrfs_root *log);
 207 void btrfs_wait_logged_extents(struct btrfs_trans_handle *trans,
 208                                struct btrfs_root *log, u64 transid);
 209 void btrfs_free_logged_extents(struct btrfs_root *log, u64 transid);
 210 int __init ordered_data_init(void);
 211 void ordered_data_exit(void);
 212 #endif